The ebb and flow of sea level rise

BBC science and nature writer Mark Kinver has a superb, informative article about sea level rise. He covers the factors that affect sea level, such as expansion from heat, more volume from ice melt, changes in ocean current, and topography.

He also explains the evolution from using old-fashioned tidal gauges to sophisticated satellite measurement, such as the Jason-2 shown here. Getting proper data can be quite challenging. He quotes from several scientists who underscore the complexities of sea level rise and the non-linear, non-global nature of many of the physical processes under scrutiny. The sea doesn't rise or fall the same amount around the world. Moreover, serious scientific attention to the interaction of all these issues is comparatively recent.

And of course the stakes are very high, since a large portion of the world's population lives in areas that are vulnerable to sea level rise and saltwater intrusion.

Image of Jason-2 satellite by NASA.